Artificial lighting in industrial countries currently consumes 27% to 40% of the electricity budget for both commercial and residential users. As a result, new ways are being sought to reduce energy consumption associated with artificial lighting. One way of reducing energy consumption is to control the lighting based on time of day, usage patterns, by agreement with the utility company, etc. Controlling artificial lighting for other reasons (e.g., architectural emphasis, security, emergency situations, visual acuity, or scene illumination) is also becoming more commonplace and may be controlled based on one or more parameters (e.g., time, user preference).
Inexpensive dimmer switches are available which may be directly connected to one or more lights for controlling the luminance level or lighting intensity output by the lights. However, these switches are typically manually operable and therefore are not effective for scene control, energy savings, or more sophisticated uses (e.g., periodic or demand-based changes) on a regular basis. In addition, these dimmer switches are typically not compatible with gas discharge lighting (e.g., fluorescent lights).
A variety of electronic regulators are commercially available for controlling the output of various types of loads. For example, lighting regulators or electronic ballasts are available for regulating the illumination level of gas-discharge lighting. Lighting regulators are typically used with sophisticated computer systems and operating software that is programmed in advance to issue luminance levels for the gas-discharge lights on a predetermined schedule. Accordingly, use is typically limited to large industrial settings where the energy savings offsets the cost of such a system.